Hello!!
Can anyone recommend a good safety knife for cable cutting? Non-conductive ceramic blade could be really useful. I did a quick research and found the Link Removed and some Link Removed by Slice. Any information about them? More options? Any recommendations on blade shape?

For cutting allegedly dead cables in order to remove them, I would test to prove dead and then "just in case" would use insulated cutters held in a gloved hand for small cables. Dependant on the degree of risk, other PPE may be prudent.
For large cables, specialist tools that "spike" or cut the cable remotely are available. Once thus proved dead, the remainder may be cut with bolt cutters or an angle grinder.

If on the other hand, jointing or similar work on live cables is being considered, then as well as proper training and PPE, I would expect that the employer would provide tools for this work.
Knives used by cable jointers normally have a standard steel blade and a moulded insulating handle. Both hooked and straight blades have their merits and I would expect both in a jointers tool kit.

I don't know many sparks who cut and strip cables using a utility knife (barring striping back the outer sheath or SWA)
I defo wouldn't be cutting live through cables with any knife even if it had a rubberised handle.
I don't think I have ever come across a knife with a ceramic blade but I'm sure that they must exist somewhere

Knives with a ceramic blade certainly exist and are sold for kitchen purposes.

As regards a knife for stripping cables, I think that this may be a USA thing ?
The American armed forces certainly used to teach that wires should be stripped with a knife. "By a whittling process, rather similar to the sharpening of a pencil. And NEVER with the knife blade or other cutting tool at right angles to the wire"
It was considered that cutting the insulation at right angles carried too much risk of nicking the conductor and consequent risk of breakage.

In the UK I have read a recommendation that small aluminium conductors should be striped as above, on account of being relatively fragile.

A great many American civilian electricians, or instructors, learnt their trade in the armed forces.
Other organisations may have taken the view that the military way was the right way.

Knives with a ceramic blade certainly exist and are sold for kitchen purposes.

As regards a knife for stripping cables, I think that this may be a USA thing ?

The American armed forces certainly used to teach that wires should be stripped with a knife. "By a whittling process, rather similar to the sharpening of a pencil. And NEVER with the knife blade or other cutting tool at right angles to the wire"

It was considered that cutting the insulation at right angles carried too much risk of nicking the conductor and consequent risk of breakage.

In the UK I have read a recommendation that small aluminium conductors should be striped as above, on account of being relatively fragile.

A great many American civilian electricians, or instructors, learnt their trade in the armed forces.

Other organisations may have taken the view that the military way was the right way.

I would only use a knife to strip larger conductors, say 10mm and up.

In America and Canada their preference is to totally strip back the cables prior to inserting in the reception box.
They then simply coil the cores up ready for 2nd fix once the dry walling and painting is complete.
I have seem their electricians lay the cable flat of the floor and spilt the cable straight down the middle using a knife then just slice off the outer sheath. They rarely use side cutters like we do. They do use big loppers (eagles beak) for cutting heavy gauge wire thou.

It may be an age thing, for those at the opposite end of the scale to the 21st century unzipping of twin and earth by using the CPC as a tin opener.
Older cloth covered VIR and so forth would be gently circumcised to cut the strands of the cloth jacket but not deep into the rubber, so not scratching the tinned copper.
Usually the old sweats used the sort of pocket knife that nowadays lands you in trouble if you forget it is in your pocket and take it down the road with no good reason, and you can't take to jobs in certain schools and similar places
There are a variety of lovely tools for stripping that don't have exposed blades, but almost any building knife will remove modern insulation.
For taking stuff out, assuming its not so big its hacksaw time, I'd reach for a tool I affectionately call my 'chompers'

Originally posted by: mapj1Older cloth covered VIR and so forth would be gently circumcised to cut the strands of the cloth jacket but not deep into the rubber, so not scratching the tinned copper.

The outer sheath of the VRI was cut, probably using a sharpened, insulated hacksaw blade, (as in my case). It had to be cut back about 12mm at terminations leaving the exposed rubber, since the sheath was considered to be hyroscopic. Not many people know that!

I note the VRI comment. In this case VIR was correct as the insulation material was Vulcanised India Rubber. For a complete cable VRI, Vulcanised Rubber Insulated can be used. Vulcanised Bitumen Insulation also existed.

I wouldn't use anything other than a Stanley knife, blunt blades = slips and cuts.

Only once in forty years have I cut myself making off a cable. Stuck in the back of an MCC panel I asked one of the electricians to pass me one of my Stanley knifes, he passed me his own, he may as well have passed me an axe.

I remember an older sparky saying he always cut the t/e with a knife and never used the cpc to yank through it, he wasn't taught that way.

I know the BT guys use a little stripping knife a lot, as one gave me his old one, it's got a small curved blade on it .

I have some Weicon self strippers , work great on the flex cables as really quick and they are designed for it , but they were expensive.

Those really cheap ones I like that are two opposed 'V's as you can strip most domestic cables including alarm and bt solid cable by feel really well.

I have bought some Knipex '6 in 1' plier looking things , they have the pre cut holes for 1.5/2.5 mm which are accurate, long nose pliers to bend the cables over, and handy for poking wires in /out of a busy board, and a larger circular cutter that will accommodate 25 mm tails, they are probably the best idea I have seen for a while.

Thank you so much for all your replies!! So much information here!!
I asked about safety knives with ceramic blades because blades are non-sparking, non-conductive... I am more worried about that kind of things. Not worried about cutting myself.

I don't know why the links I posted are not working, but I found some ceramic utility knives that looks like the kind of things I want to carry inside my pocket for everyday duties. Not only sparking things.

I also found some cable knives by a German company and they also seem so interesting but not something for using outside work.

Did you ever use some of them? I am aware that sometimes safety features are not well implemented and tools are safer but not good for working.

Legislation requires that a metal strip is bonded into the handle of a ceramic knife at manufacture.

Regards

-------------------------
"Take nothing but a picture,leave nothing but footprints!"-------------------------"Oh! The drama of it all."-------------------------"You can throw all the philosophy you like at the problem, but at the end of the day it's just basic electrical theory!"-------------------------

Oh for simpler times....
oh and as regards VIR vs VRI and books from 1925, I am
a) not that old
b) not soo worried about the abbreviations so long as we know what we are discussing.

Oh my, sharpened hacksaw blades as home made knives is a throwback.
Sort of thing I still do at home, a its a quick flick on the grinder and they take a quick edge for carving profiles and striking the back with a hammer as a hacker, but I'd never dare carry one at work.
We'll be reminiscing about how many turns of Empire Brand black cloth tape used as a handle on the things next.

Talking about old books, I recall whilst crawling around in the loft of my house I came across lengths of wood with two parallel grooves machined therein.

These turned out to be remnants of a wiring system which went under the name of The Wood Casing System. Apparently the timbers were originally fitted with a wood capping to retain the conductors in the grooves and I believe porcelain beads could be used to insulate the conductors as they emerged from the casing.

In my 1907 copy of 'Technical Electricity' it says this under the heading of 'Disadvantages of The Wood Casing System'

1. It is not fireproof; In fact it is highly inflammable
2. It is unsuited for exposed and damp situations, for it readily absorbs moisture and in this condition is really dangerous.
6 ......." the utilization of the casing for hat pegs, picture hangers, and physical developers (? eh) , the best advice that can be given is to quote that of our best friend "Punch" - DON'T

I think they mean folk doing pull-ups from it ,as the more athletic of us sometimes do by curling our fingers over the tops of door frames in a modern house.
My tip is not to do it in anyone else's house unless you are confident of the security of the architrave, or do not value the houseowners friendship. Similar things sometimes happen to steel conduit if it is at a height and spacing from the wall that it affords a good finger curl hand grip.